<!DOCTYPE html>
<html lang="en">
<head>
    <title>css阻塞</title>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <style>
        h1 {
            color: red !important
        }
    </style>
    <script>
        function h () {
            console.log(document.querySelectorAll('h1'))
        }
        setTimeout(h, 0)
    </script>
    <link href="https://cdn.bootcss.com/bootstrap/4.0.0-alpha.6/css/bootstrap.css" rel="stylesheet">
</head>
<body>
<h1>这是红色的</h1>
</body>
</html>
